Drilling mechanism



April ll, 1933. M. P. HOLMES DRILLING- MECHANISM Original Filed. June 25, 1927 i .mwN

Patented Apr. 181, 18933 Niven STATES PA'I'ENTg OFFICE MORRIS P. HOLMES, F CLAREMONT, NEW HAMPSHIRE, ASSIGNOR TO SULLIVAN MACHINERY COMPANY, A CORPORATION 0F MASSACHUSETTS D-RILLING MECHANISIVI Original application led June 23, 1927, Serial No. 200,826. Divided and this application iled. April 20,

This invention relates to drilling mechanisms and more particularly to improved rotation and feeding means for such mechanisms.

An object of this invention is to provide an improved drilling mechanism. Another' object is to provide improved rotation and feeding means for a drilling mechanism. Yet another object is to provide an improved To feeding mechanism of the differential screw type whereby the working implement may be fed positively in opposite directions at different speeds. Another object is to provide an improved feeding mechanism of the E differential screw type wherein the feeding mechanism is automatically controlled by the resistance to rotation of the Working'implement and wherein the feed is automatically reversed when the resistance to rotation exceeds a predetermined amount. Yet another object is to provideV improved rotation and feeding means for a rotary type coal drill whereby shot holes may be drilled in the mine wall in an improved manner. These and other objects and advantages of this invention will, however, hereinafter more fully appear.

In the accompanying drawing there is shown for purposes of illustration one form which the invention may assume in practice.

In this drawing,-k

Fig. 1 is a sectional view Vtaken through the longitudinal vertical center of thedrilling mechanism and illust-rating the illustrative embodiment of the improved rotating and feeding means.

` Fig. 2 is a horizontal sectional View taken substantially on line 2-2 of Fig. 1.

Fig. 8 is a detail view illustrating the 43 clutch shipper operating mechanism.

In this illustrative embodiment of the invention, which is a division of my copending application Ser. No. 200,826, filed June Y 28, 1927, there is shown a drilling mechanism 55 generally designated 1 of improved form carried by suitable supporting means 2. This supporting means herein comprises a frame 3 having pivotally mounted thereon,

A at'4, for swinging movement relative theref3 te, a frame member 5 which carries the drill Serial No. 531,424.

casing 6. Journaled in the frame 3 is a shaft 7 driving a bevel pinion 8 meshing, as shown in Fig. '2, with a bevel gear 9. This bevel gear is keyed to a shaft 10 preferably arranged with its axis alined with the frame pivot 4 and driving a bevel gear 11 meshing with a bevel gear 12. The gear 12 is fixed to a shaft 13 suitably journaled within the drill casing and driving spur gears 14 and 15 of different tooth ratio. The gear 14 meshes with a gear 16 which drives through a friction clutch 17 of a usual design the drill rotation means, While the gear 15 meshes with a spur gear 18 which drives through a similar friction clutch 19, the drill feeding means as hereinafter described.

yReferring more particularly toL the drill rotation means, it will benoted that the gear 16 is keyed to the clutch housing 20 of the clutch 17 and this housing carries a series of clutch plates interleaved with a corresponding series of clutch plates carried by a tubular spider member 21. As shown, the spider member 21 is journaled at its ends in ball bearings 22, 22 suitably supported Within the drill casing. The spider 21 has formed thereon, at its forward end, internal splines 23 which cooperate with splineways 24 formed on the outer periphery of a tubular drive member 25,'the splineways extending lengthwise of the tubular drive member, as shown. The member 25 carries at its forward end a chuck 26 of any suitable designV which receives the usual working implement 27 herein an auger drilling tool, the member 25 moving axially through the spider member 21 during feeding of the working implement, as will later be described. The friction clutch 17 is normally maintained applied by means of a coil spring 28 acting on a clutch applying member 29 and this clutch applying member is movedintoits released position by means of a pivoted shipper member 30 of a usual design. When the friction clutch 17is applied the working implement 27 is rotated through the gearing 14, 16, friction clutch 17, spider 21 and the tubular drive member 25.

As shown in the drawing, the gear 18 is keyed to the clutch housing 31 of the clutch 19 and this housing carries a series of clutch plates which are interleaved with a corresponding series of clutch plates carried by a spider member 32 similar to the spider member 21 heretofore described and this spider member 32 is mounted on and splined at 33 to a tubular drive member 34, fixed at 35 at its rear end to a feed screw 36, the latter extending centrally within the tubular drive member 25, as shown in Fig. l. The member 34 is suitably journaled on ball bearings carried by the drill casing. The member has formed integrally therewith at its rear end a feed nut 37 threadedly connected at 38 to the feed screw 36. The tubular drive member 34 has formed thereon intermediate its ends, a radial flange 39 interposed between a ball thrust bearing 4() and the adjacent ball bearing in which the tubular drive member 34 is journaled. Closing the opposite ends of the drill casing are combined cover plates and bearing retaining members 41 and 42 which each carry a suitable packing ring 43 for preventing leakage of oil from the drill casing. The feed friction 19 is normally held in its applied position by a coil spring 44 acting on a clutch applying member 45, and this clutch is released by a usual pivoted shipper member 46. As shown in Fig. 3, the shipper yokes and 46 are respectively provided with arms or levers 48 and 49 having reduced ends projecting within apertures 50 formed within the hollow hub of an operating lever 51. The lever 51 is pivotally mounted at 52 on the exterior of the drill casing. Then the lever 51 is in the mid-position shown in Fig. 3, the shipper yokes are in released position and consequently both clutches are maintained applied by the coiled springs 28 and 44. When the lever 51 is swung to the left the arm 48 is swung upwardly and the arm 49 is swung downwardly and as a result the spring 28 is compressed and the clutch 17 is released. Whenthe lever 51 is swung in the opposite direction the spring 44 is compressed and the clutch 19 is released.

Y 1n the operation of the improved drill rotation and feeding means the shaft 7 is driven from a suitable source of power, and when the drill is placed at a suitable position adjacent the working face, the operator releases the feed friction 19, and as a result, the working implement 27 is fed forwardly at a relatively high speed until it engages the coal. The drill is driven at that time through the gearing 14, 16, friction clutch 17 and the Aspider 21 splined to the tubular drive mem- -ber 25, and as a result the latter is rotated relative to the then stationary feed screw 36. After the working implement 27 is suitably positioned relative to the working face, the clutch shipper 46 is released by the operator and at that time both clutches 17 and l19 are held in their applied position by the driven through the gearings 14, 16 and 15, 18 respectively and consequently both the drive member 25 and the feed screw 36 are rotated in the same direction. As the gears 16 and 18 are of different tooth ratio, the tubular drive member 25 is rotated at a differential speed with respect to the feed screw 36. The gearing is so proportioned that when the gears 16 and 18 are simultaneously rotated, the tubular drive member 2", which carries the working implement 27, rotates at a speed materially faster than the rate of rotation of the feed screw 36, and as a result, the member 25 is fed slowly outwardly relative to the feed screw 36. After the shot hole has been drilled to the desired depth, the operator releases the rotation friction 17, and, as a result, the feed screw 36 is rotated relative to the then stationary drive member 25 and consequently the tubular drive, member is fed rearwardly at a relatively high speed. During the drilling operation, if an unduly hard substance, for instance a sulphur ball, is encountered by the working implement, rotation of the implement is resisted and when the resistance to rotation exceeds a predetermined amount, the rotation friction 17 automatically slips, and as a result, when the speed of rotation of the drive member 25 hecomes less than the speed of rotation of the feed screw 36, the working implement is automatically retracted from the face due to the differential action between the two driven elements. vWhen the working implement is again free to rotate, the speed of rotation of the member 25 is automatically increased and the working implement is again advanced towards the work at a relatively slow speed until it is again resisted, this operation being repeated automatically until the hard material is penetrated. It is therefore obvious that the possibility of breakage of the working implement is materially diminished. The various other uses and advantages of the improved drilling mechanism will be clearly apparent to those skilled in the art.

While there is in this application specifically described one form which the invention may assume in practice, it will be understood that this form of the same is shown for purposes of illustration and that the invention may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

Vhat I claim as new and desire to secure by Letters Patent is:

1. In a drilling mechanism, tool rotating and feeding mechanism comprising a plurality of coaxial driving elements, a tubular tool driving member operatively connected to one of said driving elements, a rotatable tool feeding member operatively connected to another of said driving elements and extending within said tubular driving member, means for simultaneously rotating said driving elements for effecting axial movement of said driving member relative to said feeding member in one direction, and means for alternatively driving said driving elements for effecting movement of said driving member at different speeds in opposite directions.

2. In a drilling mechanism, tool rotating and feeding mechanism including a plurality of coaxial driving elements rotatable at different speeds, a too-1 driving member operatively connected to one of said driving elements, a rotatable member operatively connected to another ofsaid driving elements, a feed screw secured to said rotatable member, a feed nut carried by said driving member and cooperating with said feed screw, and means for rotating said driving elements simultaneously or independently for effecting axial movement of said driving member` relative to said feed screw at different speeds in opposite directions.

3. In a drilling mechanism, tool rotating and feeding mechanism including a plurality of coaxial driving elements rotatable at different speeds in the same direction, al tool driving member operatively connected to one of said driving elements, a rotatable member operatively connected to another of said driving elements, a feed screw carried by said rotatable member, a feed nut carried by said driving member and cooperating with said feed screw, and means for simultaneously rotating said driving elements for effecting axial movement of said tool driving member relative to said feed screw in one direction, and means for rotating one of said driving elements while the said other driving element is inoperative for effecting axial movement of said tool driving member relative to said feed screw at a different speed in the opposite direction.

'4. In a drilling mechanism, tool rotating and feeding mechanism including a plurality of coaxial driving elements rotatable at different speeds in the same direction, a rotatable and axially movable tool driving member operatively connected to one of said driving elements, a rotatable member operatively connected to another of said driving elements, a feed screw carried by said rotatable member, a. feed nut carried by and movable axially with said tool driving member and cooperating with said feed screw, and means for simultaneously rotating said driving elements for effecting axial movement of said tool driving member at a slow speed in one direction and means fordriving one of said driving elements while thefsaid other driving element is inoperative for effecting axial movementof saidk tool driving member at a different speed in the opposite direction.

5. In a drilling mechanism, tool rotating and feeding mechanism including a plurality of coaxial driving elements rotatable at different speeds in the same direction, a tool driving member arranged coaxially with and extending through said driving elements, operative connections between one of said driving elements and said driving member for rotating the latter, and mechanism for axially feeding said driving member including a rotatable member operatively connected to another of said driving elements, a feed screw secured to said rotatable member, and a feed nut carried by said driving member and cooperating with said feed screw.

6. In a drilling mechanism, tool rotating and feeding mechanism including a plurality of driving elements rotatable at different speeds in the same direction, a tool driving member, operative connections between one of said driving elements and said tool driving member for rotating the latter, and mechanism for axially feeding said tool driving member comprising a rotatable member' operatively connected to another of said driving elements, said rotatable member being fixed against axial movement, a feed screw rigidly secured to said rotatable member, and a feed nut carried by and movable axially with said driving member and cooperating with said feed screw.

7. In a drilling mechanism, tool rotating and feeding mechanism including a plurality of driving elements rotatable at different speeds in the same direction, a tool driving member, operative connections between one of said driving elements and said tool driving member for rotating the latter, and mechanism for axially feeding said tool driving member comprising a rotatable member operatively connected to another of said driving elements, said rotatable member being fixed against axial movement, a feed screw rigidly secured to said rotatable member, a feed nut carried by and movable axially with said driving member and cooperatingwith Y said feed screw, means for Simultaneously rotating said driving elements for effecting axial feeding movement of said tool driving member in one direction and means for disconnecting the said driving element for said tool driving member from said rotating means for eecting feeding movement of the latter in the opposite direction at a different speed.

8. In a drilling mechanism, tool rotating and feeding mechanism including a plurality of driving elements rotatable at different speeds in the same direction, a tool driving member, operativeconnections between one of said driving elements and said tool driving member for rotating the latter, and mechanism for axially feeding said tool driving member comprising a rotatable member operatively connected to another of said driving elements, said rotatable member being fixed against axial movement, a feed screw rigidly secured to said rotatable member, a feed nut carried by and movable axially with Cab said driving member and cooperating with said feed screw, means for simultaneously rotating said driving elements for effecting axial feeding movement of said tool driving member in one direction, and means for disconnecting the said driving element for said rotatable member from said rotating means for effecting axial feeding movement of said tool driving member at a higher speed in the same direction. Y

9. In a drilling mechanism, tool rotating and feeding mechanism comprising a plurality of coaxial tool actuating elements, driving means therefor including continuously rotating coaxial driving gears, friction clutches coaxial with said driving gears for connecting said tool actuating elements to said driving gears, a tool rotating member connected to one of said actuating elements, a tool feeding member connected to another of said actuating elements, and means for selectively controlling said clutches to effect axial movement of said tool rotating member at different speeds in opposite directions.

l0. In a drilling mechanism, tool rotating and feedinfy mechanism comprising coaxial driving gears, a rotatable tool carrying sleeve, a rotating member connected to said sleeve and relative to which the latter is axially movable, a second rotatable sleeve, a second rotating member connected to said second sleeve to rotate the latter, a feed screw connected to said second sleeve, a feed nut carried by said firstmentioned sleeve and "i threadedly connected to said feed screw,

clutches for connecting said rotating members to said gears respectively, and means for selectively controlling said clutches to effect simultaneous or independent rotation of said sleeves to effect feed to said tool carrying sleeve at different speeds in opposite directions.

ll. In a drilling mechanism, tool rotatiiw and feeding mechanism comprising coaxia continuously rotating driving gears, a rotatable tool carrying sleeve, a rotating member connected to said sleeve, a second rotatable sleeve, a second rotating member connected to said second sleeve to rotate the latter, a feed screw connected to saidsecond sleeve and extending axially within said tool carrying sleeve, a feed nut carried by said tool carrying sleeve and threadedly connected to said feed screw, friction clutches for connecting said rotating members to said gears respectively, and means for selectively controlling said clutches to effect simultaneous or independent rotation of said sleeves to effect feed of said tool carrying sleeve at different speedsin opposite directions. Y

. l2. In a rilling mechanism, tool rotating and feeding mechanism comprising coaxially continuously rotatable drivinggears, a roatable tool carrying sleeve having lreyways extending throughout its length, a rotating member having llieys engaging said keyways, said tool carrying sleeve being movable axially relative to said rotating member, a second rotatable sleeve, a second rotating member connected to said second sleeve to rotate the latter, a feed screw secured to said second sleeve and extending axially within said first mentioned sleeve, a rotatable feed nut carried by and movable axially with said first mentioned sleeve and threadedly connected to said feed screw, clutches for connecting said rotating members to said gears respectively, and means for selectively controlling said clutches to effect simultaneous or independent rotation of said sleeves to effect feed of said tool carrying sleeve at different speeds in opposite directions.

13. In a drilling mechanism, tool rotating and feeding mechanism comprising a rotatable feed screw, a cooperating rotatable nut, said nut being movable axially relative to said screw. a tool driving member connected to and movable axially with said nut, and means for effecting simultaneous rotation of said screw and nut or for effecting rotation of one of the same relative to the other to effect feeding movement of the tool driving member at different speeds. y

lll. In a drilling mechanism, tool rotating and feeding mechanism comprising a rotatable feed screw, a cooperating rotatable nut, said nut being movable axially relative to said screw. a tool driving member connected to and movable axially with said nut, and means for effecting simultaneous rotation of said screw and nutor for effecting rotation of one of the same relative to the other to effect feeding movement of the tool driving member at different speeds in the same direction.

l5. In a drilling mechanism, tool rotating and feeding mechanism comprising coaxial relatively rotatable tubular members, one of said members being movable axially relative to the other, a feed screw fixed to and rotatable with one 0f said members, a cooperating feed nut fixed to and rotatable with the other of said tubular relatively axially movable members, a drilling tool driven by one of said members, and means for effecting rotation of said members together or for effecting rotation of one of the same relative to the other to effect axial feeding movement of said axially movable member at different speeds.

16. In a drilling mechanism, tool rotating and feeding mechanism comprising coaxial relatively rotatable tubular members, one of said members being movable axially relative to the other, a feed screw fixed to and rotatable with one of said members, a. cooperating feed nut fixed to and rotatable with the other of said tubular relatively axially movable members, a drilling tool driven by one of said members, and means for effectinfY rotation of said members together or for effecting rota tion of one of the same relative to the other to effect axial feeding movement of said axially movable member at different speeds in opposite directions.

17. In a drilling mechanism, tool rotating and feeding mechanism comprising coaxial relatively rotatable tubular members, one of said members being movable axially relative to the other, a feed screw fixed to and rotatable with one of said members, a cooperating feed nut fixed to and rotatable with the other of said tubular relatively axially movable members, a drilling tool driven by one of said members, and means for effecting rotation of said members together or for effecting rotation of one of the same relative to the other to effect axial feeding movement of said axially movable member at different speeds including a relatively high and a relatively low speed in one direction.

18. In a drilling mechanism, tool rotating and feeding mechanism including coaxial driving elements rotating in the same direction at different speeds, alined driven elements, manually operable clutches for `connecting said driven elements to their respective driving elements, a member driven by and connected to one of said driven elements for rotation therewith and for axial movement relative thereto, a drilling tool carried by said member, a feed screw rotatable with the other of said driven elements, and a cooperating feed nut secured to said tool carrying member.

19. In a drilling mechanism, tool rotating and feeding mechanism including -coaxial driving elements rotating in the Same direction at different speeds, alined driven elements, manually operable clutches for connecting said driven elements to their respective driving elements, a member driven by and connected to one of said driven elements for rotation therewith for axial movement relative thereto, a drilling tool carried by said member, a feed screw rotatable with the other of said driven elements, and a cooperating feed nut secured to said tool carrying member, said clutches being controllable to effect rotation of said feed nut while said screw remains stationary to effect one feeding speed of said drilling tool.

20. In a drilling mechanism, tool rotating and feeding mechanism vincluding coaxial driving elements rotating in the same direction at different speeds, alined driven elements, manually operable clutches for connecting said driven elements to their respective driving elements, a member driven by and connected to one of said driven elements for rotation therewith and for axial move-- ment relative thereto, a drilling tool carried by said member, a feed screw rotatable with the other of said driven elements, and a cooperating feed nut secured to said tool carrying member, said clutches being controllable to effect rotation of said feed nut while said screw remains stationary to effect one feeding speed of said drilling tool or to effect simultaneous rotation of said screw and nut at different speeds to effect a different feed- ,7

ing speed. 21. In a drilling mechanism, tool rotating and feeding mechanism including coaxial driving gears rotating in the same direction at different speeds, alined tubular drivenelements, manually controllable friction clutches for connecting said driven elements to their respective driving gears, a tubular member extending axially Within said tubular driven elements, said tubular member being rotatable su driving gears rotating in the same direction at different speeds, alined tubular driven elements, manually controllable friction clutches for connecting said driven-elements to their respective driving gears, a tubular member extending axially within said tubular driven elements, said tubularmember being rotatable with and movable axially relative to one of said driven elements, a drilling tool carried by said tubular member, a feed screw rotatable with said other tubular driven element and extending axiallywithin said tubular member, and a feed nut secured toV said tubular member, said friction clutches being controllable to effect rotation of one of said feed screw and nut elements separately relative to the other to obtain one feeding speed and to effect simultaneous rotation of said screw and nut to effect a different feeding speed.

23. In a drilling mechanism, tool rotating and feeding mechanism including a plurality of driving elements', a tool driving member operatively connected to one of said driving elements, a rotatable member operatively connected to another of said driving elements, a feed screw secured to said rotatable member, a feed nut carried vby said driving member and cooperating with .said feed screw, and means for rotating said driving elements simultaneously or independently for effecting axial movement of said driving member relative to said feed screw at different speeds in opposite directions.

24. In a. drilling mechanism, tool rotating and feeding mechanism including a. plurality of driving elements, a tool driving member operatively connected to one of said driving elements, a rotatable member operatively connected to another of said driving elements, a

feed screw carried by said rotatable member, i

lOO

a feed nut carried by said driving member and cooperating with saidfeed screw, and means for simultaneously. rotating said driving elements for effecting axial movement of said tool driving member relative to said feed screw in one direction, and means for rotating one of said driving elements while the said other driving element is inoperative for effecting axial movement of said tool driving member relative to said feed screw at a diti'erentspeed in the opposite direction.

25. In a drilling mechanism, a tool rotating and feeding mechanism including a plurality of driving elements, a rotatable and axially movable tool driving member operatively connected to one of said driving elements, a rotatable member operatively connected to another ofsaid driving elements, a feed screw carried by said rotatable member, aI feed nut carried by and movable axially with said tool driving member and cooperating with said feed screw, and vmeans for simultaneously rotating said driving elements for effecting axial movement of said tool driving member ata slon7 speed in one direction and means for driving one of said driving elements while the said other driving element is inoperative for effecting axial movement of said tool driving member at a diierentspeed in the opposite direction.

26. In a drilling mechanism, tool rotating and feeding mechanism including a plurality of driving elements, a tool driving member arranged coaxially with and extending through said driving elements, operative connections between one of said driving elements and said driving member for rotating the latter, and mechanism for axially feeding said driving member including a rotatable member operatively connected to another of said driving elements, a feed screw secured to said rotatable member. and a feed nut carried by said driving member and cooperating with said feed screw.

27. In a drilling mechanism, tool rotating and feeding mechanism including a plurality of driving elements, a tool driving member, operative connections between one of said driving elements and said tool driving member for rotating the latter. and mechanism for axially feeding said tool driving member comprising a rotatable member operatively connected to another of said driving elements, said rotatable member being fixed against axial movement, a feed screw rigidly secured to said rotatable member, and a feed nut carried by and movable axially with said driving member and cooperating with said feed screw.

28. In a drilling mechanism. a tool rotating and feeding mechanism including a plurality of driving elements, a tool driving member, operative connections between one of said driving elements and said tool driving membei' for rotating'tlie latter, and mechanism connected to another of said driving elements,

said rotatable member being fixed against axial movement, a feed screw rigidly secured to said rotatable member, a feed nut carried by and movable axially with said driving member and cooperating with said feed screw, means for simultaneously rotating said driving elements for effecting axial feeding movement of said tool driving member in one direction and means for disconnecting the said driving element for said tool ldriving member from said rotating means for effecting feeding movement of said tool driving element in the opposite direction at a different speed.

29. In a drilling mechanism, tool rotating and feeding mechanism including a plurality of driving elements, a tool driving member, operative connections between one of said driving elements and said tool driving member for rotating the latter, and mechanism for axially feeding said tool driving member comprising a rotatable member operativelyv connected to another of said driving elements, said rotatable member being fixed against axial movement, a feed screw rigidly secured to said rotatable member, a feed nut carried by and movable axially with said driving member and cooperating with said feed screw, means for simultaneously rotating said driving elements for effecting axial feeding movement of said tool driving member in one direction, and means for disconnecting the said driving element for said rotatable member from said rotating means for effecting axial feeding movement of said tool driving member at a higher speed in the saine direction.

30. In a drilling mechanism, tool rotating and feeding mechanism including driving elements, alined driven elements, manually controllable clutches for connecting said driven elements to their respective driving elements, a` member driven by and connected to one of said driven elements for rotation therewith and for axial movement relative thereto, a drilling tool carried by said member, a feed screw rotatable with the other of said driven elements, and a cooperating feed nut secured to said tool carrying member.

31. In a drilling mechanism, tool rotating and feeding mechanism including driving elements, alined driven elements, manually controllable clutches for connecting said driven elements to their respective driving elements, a member driven by and connected to one of said driven elements for rotation therewith for axial movement relative thereto, a drilling implement carried by said meniber, a feed screw rotatable with the other of said driven elements, and acooperatin g feed nut secured to said drilling implement carrying member', said clutches being controllable' to effect rotation of said feed nut while said screw remains stationary to effect one feeding speed of said drilling.implement.

32. In a drilling mechanism, tool rotating and feeding mechanism including coaxial driving elements, alined driven elements, manually controllable clutches for connecting said driven elements to their respective driving elements, a member driven by and connected to one of said driven elements for rotation therewith for axial movement relative thereto, a drilling implement carried by said member, a feed screw rotatable with the other of said driven elements, and a cooperating feed nut secured to said drilling implement carrying member, said clutches being controllable to effect rotation of said feed nut while said screw remains stationary to effect one feeding speed of said drilling implement or to effect simultaneous rotation of said screw and nut at different speeds to eect a different feeding speed.

33. In a drilling mechanism, tool rotating and feeding mechanism including driving gears, alined tubular driven elements, manually controllable friction clutches for ccnnecting said driven elements to their respective driving gears, a tubular member extending axially within said tubular driven cle ments, said tubular member being rotatable with and movable axially relative to one of said driven elements, a drilling implement carried by said tubular member, a feed screw rotatable with said other tubular driven element and extending axially within said tubular member, and a feed nut secured to said tubular member.

34. In a drilling mechanism, tool rotating and feeding mechanism including driving gears, alined tubular driven elements, manually controllable friction clutches for connecting said driven elements to their respective driving gears, a tubular member extending axially within said tubular driven elements, said tubular member being rotatable with and movable axially relative to one of said driven elements, a drilling implement carried by said tubular member, a feed screw rotatable with said other tubular driven element and extending axially within said tubular member', and a feed nut secured to said tubular member, said friction clutches being controllable to edect rotation of one of said feed screw and nut elements relative to the other to obtain one feeding speed and to effect simultaneous rotation of said screw and nut 'to effect a different feeding speed.

35. In a drilling mechanism, tool rotating and feeding mechanism including a rotatable tubular member, means for rotating said member, a rotatable tool carrying member splined to and slidable axially through said tubular member, and means for axially moving said tool carrying member including a rotatable non-axially movable feed screw and a cooperating feed nut rotatable and axially movable with said tool carrying member.

36. In a drilling mechanism, tool rotating and feeding mechanism including a tool carrying member, means for rotating said member, and means associated with said rotating means for axially moving said member including a rotatable tubular housing, means for rotating the same, and cooperating relatively movable feeding elements arranged to extend within said housing, one of which is secured to and rotatable with said tool carrying member.

37. In a drilling mechanism, tool rotating and feeding mechanism including a tubular tool carrying member, means for rotating said member, and means 'for axially moving said member including a second tubular member, means for rotating said second member, a feed screw arranged within and rotatable with said second member, and a feed nut engaging said screw and rotatable with said first member.

38. In a drilling mechanism, tool rotating and feeding mechanism including a tool carrying member, rotation means therefor, and feeding means for said member associated with said rotation means including a rotatable non-axially movable feed screw and a feed nut engaging said screw and secured to and movable axially and rotatably with said tool carrying member.

39. In a drilling mechanism, tool rotating and feeding mechanism including an axially movable tool carrying member, a rotatable non-axially movable feed screw, a rotatable axially movable feed nut engaging said screw, and means for rotating said nut relative to said screw to obtain one feeding speed of said tool carrying member and for rotating both said nut and screw at relatively different speeds to obtain another feeding speed of said tool carrying member.

40. In a drilling mechanism, tool rotating and feeding mechanism including an axially movable tool carrying member, a rotatable non-axially movable feed screw, a rotatable axially movable feed nut engaging said screw, and means for rotating said nut relative to said screw to obtain one feeding speed of said tool carrying member and for rotating both said nut and screw at relatively different speeds to obtain another feeding speed of said tool carrying member and for rotating said screw without rotation of said nut to obtain stillfanother feeding speed of said tool carrying member.

In testimony whereof I affix my signature.

MORRIS P. HOLMES. 

